From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 25890 invoked by alias); 26 Nov 2013 15:24:24 -0000 Mailing-List: contact libc-ports-help@sourceware.org; run by ezmlm Precedence: bulk List-Id: List-Subscribe: List-Post: List-Help: , Sender: libc-ports-owner@sourceware.org Received: (qmail 25867 invoked by uid 89); 26 Nov 2013 15:24:19 -0000 Authentication-Results: sourceware.org; auth=none X-Virus-Found: No X-Spam-SWARE-Status: No, score=-1.5 required=5.0 tests=AWL,BAYES_50,RDNS_NONE,SPF_HELO_PASS,SPF_PASS,URIBL_BLOCKED autolearn=no version=3.3.2 X-HELO: mx1.redhat.com Received: from Unknown (HELO mx1.redhat.com) (209.132.183.28) by sourceware.org (qpsmtpd/0.93/v0.84-503-g423c35a) with ESMTP; Tue, 26 Nov 2013 15:24:18 +0000 Received: from int-mx10.intmail.prod.int.phx2.redhat.com (int-mx10.intmail.prod.int.phx2.redhat.com [10.5.11.23]) by mx1.redhat.com (8.14.4/8.14.4) with ESMTP id rAQFO9Dl000859 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=OK); Tue, 26 Nov 2013 10:24:10 -0500 Received: from [10.3.113.12] ([10.3.113.12]) by int-mx10.intmail.prod.int.phx2.redhat.com (8.14.4/8.14.4) with ESMTP id rAQFO9qX016819; Tue, 26 Nov 2013 10:24:09 -0500 Message-ID: <5294BD18.40507@redhat.com> Date: Tue, 26 Nov 2013 15:41:00 -0000 From: "Carlos O'Donell" User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:24.0) Gecko/20100101 Thunderbird/24.1.0 MIME-Version: 1.0 To: Will Newton , libc-ports@sourceware.org CC: Patch Tracking Subject: Re: [PATCH] aarch64: Enable ifunc support. References: <5294628E.30507@linaro.org> In-Reply-To: <5294628E.30507@linaro.org> Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit X-IsSubscribed: yes X-SW-Source: 2013-11/txt/msg00060.txt.bz2 On 11/26/2013 03:57 AM, Will Newton wrote: > > Add support for handling the R_AARCH64_IRELATIVE relocation and > STT_GNU_IFUNC symbols to the aarch64 port. How did you test this? > ports/ChangeLog.aarch64: > > 2013-11-25 Will Newton > > * sysdeps/aarch64/dl-irel.h: Include ldsodefs.h. > (ELF_MACHINE_IRELA): Define. (elf_ifunc_invoke): Pass > hwcap to ifunc resolver function. (elf_irela): New function. > * sysdeps/aarch64/dl-machine.h: Include dl-irel.h. > (elf_machine_rela) Handle STT_GNU_IFUNC symbols and > R_AARCH64_IRELATIVE relocations. (elf_machine_lazy_rel): > Handle R_AARCH64_IRELATIVE relocations. > --- > ports/sysdeps/aarch64/dl-irel.h | 22 +++++++++++++++++++--- > ports/sysdeps/aarch64/dl-machine.h | 20 ++++++++++++++++++++ > 2 files changed, 39 insertions(+), 3 deletions(-) > > diff --git a/ports/sysdeps/aarch64/dl-irel.h b/ports/sysdeps/aarch64/dl-irel.h > index 1a3811e..f37ee39 100644 > --- a/ports/sysdeps/aarch64/dl-irel.h > +++ b/ports/sysdeps/aarch64/dl-irel.h > @@ -22,15 +22,31 @@ > > #include > #include > +#include > > -/* AArch64 does not yet implement IFUNC support. However since > - 2011-06-20 provision of a elf_ifunc_invoke has been mandatory. */ > +#define ELF_MACHINE_IRELA 1 OK. > > static inline ElfW(Addr) > __attribute ((always_inline)) > elf_ifunc_invoke (ElfW(Addr) addr) > { > - return ((ElfW(Addr) (*) (void)) (addr)) (); > + return ((ElfW(Addr) (*) (unsigned long int)) (addr)) (GLRO(dl_hwcap)); OK. > +} > + > +static inline void > +__attribute ((always_inline)) > +elf_irela (const ElfW(Rela) *reloc) > +{ > + ElfW(Addr) *const reloc_addr = (void *) reloc->r_offset; > + const unsigned long int r_type = ELFW(R_TYPE) (reloc->r_info); > + > + if (__glibc_likely (r_type == R_AARCH64_IRELATIVE)) > + { > + ElfW(Addr) value = elf_ifunc_invoke (reloc->r_addend); > + *reloc_addr = value; > + } > + else > + __libc_fatal ("unexpected reloc type in static binary"); > } OK. > > #endif > diff --git a/ports/sysdeps/aarch64/dl-machine.h b/ports/sysdeps/aarch64/dl-machine.h > index 71dd6b3..01a214f 100644 > --- a/ports/sysdeps/aarch64/dl-machine.h > +++ b/ports/sysdeps/aarch64/dl-machine.h > @@ -23,6 +23,7 @@ > > #include > #include > +#include > > /* Return nonzero iff ELF header is compatible with the running host. */ > static inline int __attribute__ ((unused)) > @@ -243,6 +244,12 @@ elf_machine_rela (struct link_map *map, const ElfW(Rela) *reloc, > struct link_map *sym_map = RESOLVE_MAP (&sym, version, r_type); > ElfW(Addr) value = sym_map == NULL ? 0 : sym_map->l_addr + sym->st_value; > > + if (sym != NULL > + && __glibc_unlikely (ELFW(ST_TYPE) (sym->st_info) == STT_GNU_IFUNC) > + && __glibc_likely (sym->st_shndx != SHN_UNDEF) > + && __glibc_likely (!skip_ifunc)) > + value = elf_ifunc_invoke (value); OK. > + > switch (r_type) > { > case R_AARCH64_COPY: > @@ -331,6 +338,12 @@ elf_machine_rela (struct link_map *map, const ElfW(Rela) *reloc, > } > break; > > + case R_AARCH64_IRELATIVE: > + value = map->l_addr + reloc->r_addend; > + value = elf_ifunc_invoke (value); > + *reloc_addr = value; > + break; OK. > + > default: > _dl_reloc_bad_type (map, r_type, 0); > break; > @@ -374,6 +387,13 @@ elf_machine_lazy_rel (struct link_map *map, > td->entry = (void*)(D_PTR (map, l_info[ADDRIDX (DT_TLSDESC_PLT)]) > + map->l_addr); > } > + else if (__glibc_unlikely (r_type == R_AARCH64_IRELATIVE)) > + { > + ElfW(Addr) value = map->l_addr + reloc->r_addend; > + if (__glibc_likely (!skip_ifunc)) > + value = elf_ifunc_invoke (value); > + *reloc_addr = value; OK. > + } > else > _dl_reloc_bad_type (map, r_type, 1); > } > Looks good to me as long as your testing makes sense. Cheers, Carlos.